CS221917B2 - Method of making the dianphormaldehyde resins,hardenable by heat - Google Patents

Description

It is an object of the present invention to provide a process for the production of heat curable dianformaldehyde resins. These resins are produced by condensation of formaldehyde with waste by-products, which are lost in the known production of diane by reaction of acetone with phenol using a resin cation exchange resin as a catalyst. Hereinafter, this process is referred to as an ion exchange process. These resins are characterized by a low phenol content and can therefore be used in the production of adhesives and binders for wood and particle board as well as fiberboard.

It is known from Polish Patent Specification No. 57,393 to produce heat-curable resins from mother liquors which are discarded as a by-product in the manufacture of dian in the presence of acid catalysts.

According to this process, formaldehyde is condensed with mother liquors containing 70 to 80% by weight, phenol and in addition 10 to 15% by weight, diane isomers as well as decomposition products of catalysts used in diane production.

Although the resins produced by this method have a low phenol content and can be used for the production of adhesives, the storage stability of these resins decreases with increasing time due to the strong tendency to increase viscosity.

During further experiments concerning the production of thermosetting resins and usable for the production of adhesives, it has surprisingly been found that the process according to the invention can produce resins of the same or even better quality, which at the same time exhibit greater storage stability.

The essence of the process for the production of heat-curable dianformaldehyde resins by condensation of a 2C to 40% aqueous formaldehyde solution with waste byproducts leaving off the manufacture of diane is that waste by-products containing 0.01-10% by weight, ο, ο-dianu , which are eliminated in the production of diane by the reaction of acetone with phenol in the presence of cation exchangers, are converted into an aqueous alkaline solution, which is condensed with formaldehyde, to 100 parts by weight, after a possible, preferably catalytic decomposition in the presence of strong bases or hypophosphites. The waste by-products will use 100 to 200 parts by weight of a formaldehyde solution containing 20 to 40% by weight of formaldehyde.

Advantageously, when transferring waste by-products into an alkaline solution, phenol-containing waste water is used instead of water in the manufacture of diane.

Of the strong bases, for example, sodium hydroxide is suitable for the catalytic decomposition, or the catalytic decomposition can also be carried out in the presence of sodium bicarbonate. Both sodium hydroxide and sodium bicarbonate are used in an amount of 0.1 to 5% by weight, based on the weight of the by-products of the dianno production. The catalytic decomposition carried out in the presence of these substances is described, for example, in USSR Authorization No. 303 314, and the catalytic decomposition carried out in the presence of sodium hypophosphites (0.01 to 5% by weight, based on the weight of the by-products falling from dianu production). No. 103,054 and Przemysl Chemiczny, No. 4, p. 196 (1979).

In both cases, the catalytic decomposition is carried out at elevated temperature and low pressure.

The average composition of waste byproducts falling off in the manufacture of dian (based on the ion exchange method) is further indicated before the catalytic decomposition and after the catalytic decomposition of the by-products.

% content in% wt.

prior to catalysis of waste by-products following the decomposition of waste by-products phenol 0.1 to 10 0.01 to 5 p, p-dian 1 to 40 0.1 to 25 s, p-lial 0.1 to 10 0.1 to 5 kocHmérX) 5 to 20 5 to 20 sum of many components with a boiling point higher than p, pian 10 to '30 10 to 30 the sum of the amounts of the components whose boiling point is lower than the boiling point of the [beta] -dian 1 to 10 1 to 10 resin components 10 to 40 30 to 70

X) = dimer of ρ, ρ-dianu and ο, ρ-dianu.

At the same time, it has been found that for pretreatment of an aqueous alkaline solution of waste by-products corresponding to diane (ion exchange) production, preferably phenolic-containing waste water may be used instead of water.

The process according to the invention therefore has the advantage that waste by-products resulting from the manufacture of dian (based on the ion exchange method), which have hitherto been regarded as worthless and incinerated, are now utilized, while at the same time achieving significant cost savings phenol. This is of great importance since today the heat-curable resin-based adhesives are mainly produced on the basis of phenol. Furthermore, the use of phenol-containing effluents in the process according to the invention significantly improves the water-balance of the water, since the phenol content of the effluents is reduced (phenol is very dangerous for the environment .

The thermosetting resins produced by the process of the present invention exhibit low viscosity as well as very good storage stability, thereby facilitating significant storage and shipping.

Due to these properties, as well as good water dilutability and low phenol content, these resins are particularly suitable for gluing particleboard and fiberboard.

Solutions of these resins in organic solvents can be used as glues for wood and wood-like materials, and can be cold or hot cured in water. The catalysts are known per se. Example 1

To tříhrUé round bottom flask fitted with stirrer, tepooměrem and reflux condenser (with a volume of · 2000 ml) was NAHT 60 ^{g of} 15% isuts ^to j sodium ^hydroxide, Otom heated to ⁷⁰ ° C and then added with stirring 360 g of waste secondary of the product evaporating in the manufacture of dian (ion exchange method). The waste product contained 8.2% by weight, ^feιο-35, 6% w ^ p-palm and ^7.9 wt% · ^{ο, ρ} - ^l idlj ^Zaire ee ^ ¹⁸⁰ ° C.

258 g of the alkali solution of the waste by-product thus obtained were introduced into a 1000 ml three-necked flask equipped with a stirrer, a thermometer and a reflux condenser and 175 g of formaldehyde solution containing 20 to 40% formaldehyde were added thereto. .

Then the mixture was heated to boiling (90-95 ° C) and kept boiling until the corresponding viscosity was reached, about 15 minutes. 4 g of formaldehyde solution containing 20 to 60% formaldehyde and 8 g of water were then poured into the flask and the whole cooled.

The finished dianformaldehyde resin product was tacky and colored cherry red to brown and exhibited the following properties:

dry matter viscosity free phenol content

1.25 Pa.s 38.7 wt.%, Below 0.05 wt.

Stability during storage at room temperature was longer than 4 months.

Example 2

258 g of the alkaline waste by-product solution, which was discarded in the manufacture of diane (ion exchange method) pretreated as in example 1, were introduced into a three-necked round flask equipped as in example 1. This waste by-product was pre-treated by catalytic decomposition in presence of 0.2% by weight (based on the weight of by-products of dianu production) of sodium hydroxide at 200 ° C and at a pressure of 6.65 kPa and contained 0.1% by weight of phenol, 0.15% by weight, ρ, ρ % Diana and 0.2 wt. o, p-dianu.

After heating up to 40 ° C, 100 g of formaldehyde solution containing 20 to 40% by weight of formaldehyde was poured. The condensation process was then conducted as in Example 1. The resin produced exhibited the following properties:

viscosity 6.70 Pa.s dry matter 39.4% by weight, free phenol content below 0.05% by weight stability during storage at room temperature for more than 4 months.

Example 3

In a three-neck flask equipped as in Example 1, 490 g of phenol-containing waste water was poured and 210 g of 40% sodium hydroxide solution were added with stirring. To this mixture, heated to 85-90 ° C, was slowly mixed 360 g of the by-product waste that was lost in the manufacture of dian (ion-exchange). This waste product was pre-treated by catalytic decomposition in the presence of 0.2% by weight (based on the weight of the by-products of diane production) of sodium hypophosphite at 200 ° C and 1.33 kPa and contained 0.75% %, phenol, 1.5 wt.%, ρ, ρ-dianu and 0.6 wt. o, p-dianu.

258 g of the by-product alkaline waste by-product thus prepared were introduced into a flask equipped as in Example 1 and after heating to 40 ° C 150 g of formaldehyde solution containing 20 to 40% by weight of formaldehyde were mixed. The condensation process was then carried out exactly as in Example 1. The resin produced exhibited the following properties:

viscosity dry matter free phenol content 2,5 Pa.s 39% 0.05 wt

stability during storage at room temperature for more than 4 months

Example 4

A reactor (2,000 m) equipped with a stirrer, reflux condenser, temperature controllers and heating mantle was charged with 916 kg of phenol-containing waste water, and then 396 kg of 40% sodium hydroxide solution was added with stirring. To this mixture heated to 7 ⁰ ° C and slowly rearward introduced ^{752 kg} Toven ^ oo ^d fits vedlejSíto ^h o ^p roducts, odpadajícího manufacturing Diana (method based on ion exchange). These waste products were pre-treated by catalytic decomposition at a concentration of 0.3% hmoo. (based on hmoonost side waste products from the production of bisphenol) of sodium hypophosphite at 220 ° C and a button on ^{y 2 3} 99 ^YP AA contained ^{0, 01% of} MO · ^{h phenol, 19.7%} mot ^{h. p. p-} dianu and 2.7% hmoo. o, p-dianu.

645 kg of the byproduct of this by-product solution were fed into a 2000 L reactor equipped with a stirrer, reflux condenser and temperature regulator, as well as a heating and cooling jacket, and then 30 kg of 40% sodium hydroxide solution and 310 ml were slowly added. kg of formaldehyde solution containing 20 to 40% formaldehyde. When the temperature in the reactor rises ^ la at ⁸⁰ ° C, ^p occiput r.ovedeno first stonovení vis Ozitech ^{y y.} The determination was performed on the basis of the resin outlet time from the glass pipette (5 ml volume, outlet cross section = 3 mm). The mixture in the reactor was heated to boiling and then kept boiling until a viscosity was reached at which the resin flowed out of the capillary in 6 seconds. At this point, the addition of 10 liters of formaldehyde solution containing 20 to 40% formaldehyde and 16 liters of water interrupted the condensation process and the mixture was cooled. After reaching a temperature of 4 ⁰ C occiput to realctoru soft damp .Mtrů ^{10 and} 25% dmooia alni water.

viscosity 1.90 Pa.s dry matter 39.1 wt.

freehofenol content below 0.05 wt.

stability during storage at room temperature for more than 4 months.

This tulle resin was diluted with water (1:10) and used to resize the particle board.

Claims (2)

CLAIMS 1. A process for the production of heat-curable dihydroxy resins by condensation of a 20 to 40% aqueous solution of phosphate with waste by-products evaporating in the manufacture of diane by the fact that the waste by-products occupy from 0.01 to 10%. %, phenol, 0.1 to 40 wt. Diane and 0.1 to 10% by weight of O 2 -diane, which are evaporated in the dianion by reaction of acetone with phenol in the presence of cation exchangers, are converted, if appropriate, to a third decomposition in the presence of strong bases or alkali metal hypophosphites. aqueous solution, which is condensed with formaldehyde, wherein 100 to 200 parts by weight of formaldehyde solution containing 20 to 40% by weight of the by-product waste are used per 100 parts by weight of the by-product waste form; 2. Process according to claim 1, characterized in that waste water is used instead of water in the production of diane in the production of diane.