JPH0139449B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a novel water-soluble cationic polymer.

Cationic polymers have more adsorption active sites in their molecular chains than inorganic flocculants that have the same charge neutralization function, so they have superior performance as water treatment agents, such as using less and generating less sludge. have. For this reason, in recent years, many cationic polymers have been widely used as flocculants, replacing conventional inorganic flocculants, for clarification or decolorization of wastewater.

Examples of such cationic polymers include epichlorohydrin/ammonia polycondensates (Japanese Patent Publication No. 38-26794), polycondensates of polyalkylene polyamines and epihalohydrin (Japanese Patent Publication No. 38-26794),
20741), polycondensate of secondary amine and epichlorohydrin (Special Publication No. 49-37440, Special Publication No. 51-22471),
Polycondensates of dicyandiamide and formaldehyde are known.

However, these polymers have drawbacks such as high chemical costs, difficulty in obtaining sufficiently large molecular weights, and poor coagulation performance.

The present inventors have conducted extensive research aimed at developing an inexpensive cationic polymer that does not have these drawbacks, and as a result, have arrived at the present invention.

That is, the present invention provides compound (1) [In the formula, R ₁ and R ₂ each represent an alkyl group having 1 or 2 carbon atoms] (2) Epihalohydrin (3) Urea (4) Formaldehyde and a substance that generates it are polycondensed. The present invention relates to a method for producing a novel water-soluble cationic polymer.

To explain the present invention in detail, the aminomethyl compound of phenol represented by the general formula (1) used as a raw material (hereinafter referred to as aminomethylated phenol) contains 2 moles of formaldehyde and 2 moles of formaldehyde per mole of phenol. It is prepared by adding moles of a dialkylamine and causing a Mannitz reaction. Further, the dialkylamine used here is preferably one of dimethylamine, diethylamine, methylethylamine, or a mixture thereof from the viewpoint of reactivity. The temperature of Mannitzch reaction is
It is selected from the range of 10° to 80°C, but at low temperatures it is necessary to lengthen the reaction time, and at high temperatures the dialkylamine is likely to volatilize, so the temperature is usually 30° to 60°C.
It is preferable to react at a temperature of 3 to 6 hours.

The epihalohydrin of compound (2) includes epichlorohydrin and epibromohydrin, with epichlorohydrin being preferred. The amount of epihalohydrin to be charged is usually preferably 0.5 mol per 1 mol of aminomethylated phenol, but it can be increased to 0.8 mol in consideration of reactivity.
If it is less than this range, no polymer will be produced, and if it is more than this range, it will form a three-dimensional network structure and become water-insoluble.

Next, the amount of urea to be charged is usually preferably 0.5 to 1.0 mol per 1 mol of aminomethylated phenol. If the amount is less than this range, a polymer with good performance cannot be obtained, and if it is more than this range, the produced polymer will not be water-soluble.

Further, the amount of formaldehyde to be charged is suitably a number of moles corresponding to the sum of 1/2 of the number of moles of aminomethylated phenol and the number of moles of urea.

The polycondensation reaction is carried out by first polycondensing aminomethylated phenol and epihalohydrin, then charging urea and formaldehyde, lowering the pH to 4 or less, and heating at 50 to 80°C for 1 to 5 hours. . The amount of acid at this time may be any amount necessary to bring the pH of the system to 4 or less, and the type of acid is not particularly limited. In addition, for polycondensation, in addition to using aminomethylated phenol, predetermined amounts of phenol, dialkylamine, urea, and formaldehyde are charged, and after the Mannitz reaction occurs in the phenol, epihalohydrin is polycondensed. Furthermore, it is also possible to perform this by lowering the pH to 4 or less and heating.

It is presumed that the polymer thus obtained contains at least a repeating unit having the following structure.

[The symbols in the formula have the same meanings as in formula (1) above. Z represents an anion. As shown in the examples below, the polymer of the present invention has an effect that is superior to dicyandiamide and formaldehyde polycondensates as a flotation and sedimentation aid for dyeing industry wastewater, particularly in reducing the residual color rate. It is truly surprising that the polymer of the present invention has such excellent functionality despite its inferior cation density. The reason for this is interpreted to be an increase in polymer hydrophobicity due to the binding of urea.

Next, the present invention will be specifically illustrated by examples.
The present invention is not limited to the following examples unless it exceeds the gist thereof.

Example 1 81.1 g (1.0 mol) of 37% formaldehyde was placed in a separable flask, and 90.0 g (1.0 mol) of 50% dimethylamine was added dropwise to the flask while stirring and cooling with cold water. After completing the dropwise addition of dimethylamine, 52.2 g (0.5 mol) of 90% phenol was added, and a Mannitz reaction was carried out at 55° C. for 5 hours. Reaction product at 35℃
23.1 g (0.25 mol) of epichlorohydrin was gradually added dropwise, and the mixture was reacted at 40° C. for 5 hours. After the reaction, 15.0 g (0.25 mol) of urea, 37
% Formaldehyde 40.5g (0.5mol) was prepared,
Furthermore, 78.2 g (0.75 mol) of 35% hydrochloric acid was added, and 70
After being kept at ℃ for 1 hour, it was cooled to obtain a product. The viscosity of this product at 25°C was 70 cp using a Bruckfield viscometer.

Example 2 15.0 g (0.25 mol) of urea and 121.6 g (1.5 mol) of 37% formaldehyde were placed in a separable flask, and after the urea was dissolved, 90.0 g (1.0 mol) of 50% dimethylamine was added dropwise under stirring and cooling. . After completion of dimethylamine dropping, 52.2g of 90% phenyl
(0.5 mol) was added, heated to 55°C, and subjected to Mannitz reaction for 4 hours. The reaction product was further cooled to 35°C, and 23.1 g (0.25 mol) of epichlorohydrin was added.
was slowly added dropwise, and then kept at 40°C and reacted for 2 hours. Then add 78.2g of 35% hydrochloric acid to the reaction product.
(0.75 mol) and kept at 70°C for 1 hour,
The product was obtained after cooling. The viscosity of this polycondensate at 25°C was 130 cp.

Example 3 Performance tests were conducted using the polycondensates prepared according to the above examples and commercially available polymers.
The polymers used are as follows.

Sample A Product of Example 1 Sample B 〃 2 〃 Sample C Polycondensate of dimethylamine and epichlorohydrin (commercial product) Sample D Polycondensate of dicyandiamide and formaldehyde (commercial product) Artificial dyeing wastewater (Direct First) Prepare scarlet (300ppm solution) and bentonite
250ppm and a polymeric anionic polymer of 1ppm, a clear supernatant liquid (residual color rate 1
% or less). The minimum addition amount of each sample at that time was as follows.

Sample minimum addition amount Sample A 155ppm 〃 B 145ppm 〃 C (Residual color rate does not fall below 1%) 〃D 150ppm

Claims (1)

[Claims] 1 Compound (1) [In the formula, R ₁ and R ₂ each represent an alkyl group having 1 or 2 carbon atoms] (2) Epihalohydrin (3) Urea (4) Formaldehyde and a substance that generates it are polycondensed. A new method for producing water-soluble cationic polymers.