JPS6128506A - Production of water-soluble cationic polymer composition - Google Patents

Abstract

PURPOSE:To produce economically the titled polymer composition which is excellent in cohesive force and yet stable in a state of an aqueous solution, by reacting a cation-modified water-soluble carbamoyl group-containing polymer with a specified organic compound. CONSTITUTION:A cation-modified water-soluble polymer is formed by reacting a carbomoyl group-containing water-soluble polymer [e.g., (meth)acrylamide (co)polymer] with an alkali hydroxide (e.g., NaOH) and a hypohalite (e.g., sodium hypohallte) in an aqueous medium. The obtained polymer is reacted with a compound of the formula (wherein X is chlorine, bromine or iodine, Y is an anion of strong inorganic acid and R1, R2, and R3 are each an alkyl group), e.g., 3-chloro-2-hydroxypropyltrimethylammonium chloride.

Description

DETAILED DESCRIPTION OF THE INVENTION Today, many water-soluble polymers are used as coagulants, clarification, and promotion of dewatering at public expense for wastewater treatment, and in the paper industry to strengthen paper strength and improve drainage. Applications such as subsequent recovery), surface treatment agents, and dispensing agents are becoming more widespread year by year. At the same time, there is an increasing demand for the supply of fine-grained water-soluble polymers tailored to various uses. These water-soluble polymers are generally nonionic or nonionic due to their ionic nature.
It is classified as 1-ionic and cationic. Regarding the cationic nature of these water-soluble polymers, a large number of water-soluble polymers have been proposed using a wide variety of raw materials and modification methods, but each has its own advantages and disadvantages.

On the other hand, there are many research reports on the Hofmann decomposition reaction of polyacrylamide, which is a polymer having a carbamoyl group, but there are many problems in terms of practical application, and a fully satisfactory practical product has not yet been obtained.

Possible reasons for this are: 1. If the reaction is carried out at a high concentration, gelation tends to occur, making it impossible to obtain a highly concentrated and highly aminated product. 2. Hydrolysis tends to occur and a large amount of carboxyl groups are produced. 3. , the aqueous solution of the reaction product is extremely unstable, the degree of cationicity decreases significantly over time, and the molecular weight is lowered due to cleavage of the 4 main chains.

These phenomena are caused by gelation due to the formation of urea bonds shown in the above formula (1),
Theoretically, this can be explained by the formation of a carboxyl group by hydrolysis with an alkali as shown in the above formula (2), the oxidation reaction by a hypohalite, or the interaction between an amino group and a carboxyl group, but these are so-called side effects. Since many reactions proceed, it is extremely difficult to obtain the desired product, and although it is possible to produce a small amount experimentally, it is unsuitable on an industrial scale.

Therefore, the present invention was achieved as a result of intensive research aimed at commercializing a cationic modified product that is stable in aqueous solution and has particularly excellent cohesive strength.

The fourth aspect of the present invention is characterized in that a water-soluble polymer having a carbamoyl group is cationically modified by the action of an alkali hydroxide and a hypohalite in an aqueous solvent, and then a substance represented by the general formula is reacted with the water-soluble polymer. The present invention relates to a method for producing a water-soluble cationic polymer composition having an ammonium salt.

The water-soluble polymer having a carbamoyl group may be a polymer of acrylamide or methacrylamide or a copolymer of these and other monomers.

In the present invention, "general formula N7-R2H, ~R3; an inorganic acid salt of a tertiary amine represented by an alkyl group,"
It is obtained by reacting with epihalohydrin represented by the general formula.

Examples of tertiary amines include 6S such as trimethylamine, triethylamine, dimethylbenzylamine, dimethylcyclohexylamine, pyridine, H-methylmorpholine, and N-methylpiperidine. As a reaction product of these inorganic acid salts of tertiary amines and epihalohydrin, for example, 3
-Chloro-2-t-droxypropyltrimethylammonium chloride (reaction product of trimethylamine hydrochloride and epichlorohydrin), 3-chloro-2-toxypropyl trimethylammonium chloride (reaction product of triethylamine hydrochloride and epichlorohydrin), or N- (3-chloro-2-human tetraxypropyl) pyridinyl tetrahydrin (reaction of pyridine hydrochloride and epichlorohydrin), and similar reactants thereof (these are referred to as quaternary) 10hydrins).

The Hofmann decomposition reaction of polyacrylamide is indicated by H2 and is said to go through the steps (I) and (IV).

``The details of the reaction mechanism of the present invention are unclear, but
Estimated by experiment, it is as follows. That is, it is estimated that the quaternary halohydrin produced by Hoffmann decomposition reacts, and some of it produces a polymer having a quaternary ammonium salt, and some of it produces polyvinylamine.

In carrying out the present invention, the Hofmann fraction m reaction is performed using Na0C1 for 2 moles of NaOH.
Considering 1 mol as a standard, it is preferable to conduct the test at a temperature as low as 15°C or lower.
The blending ratio of a0C1 is PAM/Na0Cl = 50/
It is possible to have a molar ratio of 50 to 99/1, and the ratio may be selected depending on the desired polymer. However, it is not preferable to add more than the theoretically equivalent mole because polymer deterioration due to main chain scission will be significant. The quaternary halohydrin may be used in an amount equal to or less than the mole of Na0C1, preferably N
a0C1/0C1 Rohidri:/=50/ 50~90
/10 (molar ratio) is good. If more than the same molar amount is added, gelation of the polymer may occur.

The advantages of the present invention are that, compared to other cationic water-soluble polymers, (1) a cationic polymer can be obtained using relatively inexpensive raw materials;

(2) It can be used as a method for stabilizing Hofmann decomposition products, which have conventionally had extremely poor stability.

(3) Obtaining a modified product with a high molecular weight by conventional Hoffmann degradation (although this was more difficult, it is possible by using water droplets).

(4) By appropriately selecting the formulation, this product can be used as a flocculant for wastewater treatment, a dehydrating agent, various papermaking agents (freeness improver, pigment fixing agent, size fixing agent, paper strength enhancer), surface It can be widely used for processing polymers, etc.

(5) This product can also be used after being powdered using existing methods.

(Example 1) A polyacrylamide aqueous solution having a polymer concentration of 7% and an intrinsic viscosity (v''l=8.5) was polymerized using a Redox-based initiator.

1875 parts by weight of the obtained 7% polyacrylamide aqueous solution was charged into a 500 ml jacket 1 polymerization vessel equipped with a stirrer, and the inside of the jacket was maintained at 8° C. while stirring. The temperature of the system is 10
9.24 parts by weight of Jum and sodium hypochlorite (available chlorine amount 12%) 66
Part by weight is added, reacted at 10° C. for 2 hours, and further raised to 25° C. and reacted for 2 hours. 3-chloro o-2-
12.5 parts by weight of hydroxypropyltrimethylammonium chloride was added and reacted at 35°C for 1 hour.

The obtained viscous liquid polymer had a pH of 10 and a solid content of 15.
．． 0%, total cations 1.8 meg/gr, quaternary cations 0.7 meg/gr, and showed strong cohesive force for organic suspensions. The same polymer was subjected to a aging aging test using a gear type aging tester under conditions of 50° C. and 24 hours, but it was stable, did not gel, and showed almost no decrease in potency.

(Example 2) An aqueous solution of polyacrylamide/acrylic acid=9515 (mol) copolymer with a polymer concentration of 10% and an intrinsic viscosity (RI) of 2.5 was polymerized using a Redox-based initiator. Obtained polyacrylamide 10% aqueous solution 187.5
The weight part was charged into a 500 ml jacket and a polymerization vessel equipped with a stirrer, and the mixture was cooled while stirring, and the inside of the jacket was maintained at 5°C.

While keeping the temperature of the system below 8℃, add sodium hydroxide to
14 parts by weight and sodium hypochlorite (available chlorine amount 12
%) was added and reacted at 10°C for 2 hours, and then the temperature of the system was raised to 25°C and reacted for 2 hours.

24 parts by weight of 3-di-4-2-hydroxypropyl triethylammonium chloride was added, and the mixture was reacted at 35°C for 2 hours.

The obtained polymer had a pH of 10, solid content of 18%, total cations of 1.2 meg/gr, and quaternary cations of 0.3 me.
g/g rs Anionization degree was 0.3 meg/gr.

The obtained polymer was stable for 3 months at room temperature, and its potency hardly decreased.

(Example 3) A polyacrylamide aqueous solution having a polymer concentration of 5% and an intrinsic viscosity [7] of 12.5 was polymerized using an azo initiator. Obtained polyacrylamide 5% aqueous solution 187
．． 5 parts by weight were charged into a 500 ml polymerization vessel equipped with a jacket and a stirrer, and the inside of the jacket was maintained at 8°C while stirring. While keeping the temperature of the system below 10℃, add 5.7% of sodium hydroxide.
2 parts by weight and sodium hypochlorite (available chlorine amount 12%
) 40.8 parts by weight was added and reacted at 10°C for 2 hours,
Furthermore, the temperature of the system was raised to 25° C. and the reaction was allowed to proceed for 2 hours.

7.7 parts by weight of 3-chloro-2hydroxypropyltrimethylammonium chloride tetralide was added, and the mixture was reacted at 35°C for 1 hour. The obtained tone liquid polymer has a pH==-
10. Solid content 11.5%, total cations 1.2 meg/g
r, quaternary cation o,, amag/gr, and showed strong cohesive force for organic suspensions.

In addition, the polymer was tested at 50°C using a gear aging tester.
A aging aging acceleration test was conducted under the conditions of 24 hours, but it was stable, did not gel, and had almost no decrease in titer.

(Comparative Example A) A Hofmann reaction was carried out in the same manner as in Example 1, and a product without the addition of 3-chlorot2-2- and trimethylammonium chloride was prepared.

This shows excellent flocculation performance immediately after the reaction, but the titer decreases markedly over time.

Change in cohesive force due to aging O: Yes Δ: Slightly present
00PPM, organic matter = 89.8%, inorganic matter = 102%
The porin of Example 1 was added to the sample, and a dehydration test was conducted using a centrifugal dehydrator. The results are shown below.

Claims (1)

[Claims] After a water-soluble polymer having a carbamoyl group is cationically modified by the action of an alkali hydroxide and a hypohalite in an aqueous solvent, there are general formulas ▲ mathematical formulas, chemical formulas, tables, etc. ▼ A method for producing a water-soluble cationic polymer composition, characterized by reacting a substance represented by: