JPH086008B2 - Aqueous dispersion of substituted succinic anhydride - Google Patents

Description

The present invention relates to an aqueous dispersion of substituted succinic anhydride, which comprises:
In particular, it has an excellent sizing effect and good operability in applications as a sizing agent used in the paper manufacturing process, and
It is intended to provide an aqueous dispersion of a substituted succinic anhydride that exhibits an excellent action in terms of dilution stability.

[Prior Art] It is well known that an aqueous dispersion of a substituted succinic anhydride is used as a sizing agent, and there are various proposals regarding the type of the aqueous dispersion. For example, an aqueous solution of cationic starch and a substituted succinic anhydride are mixed under strong mechanical stirring,
A homogenized product (Japanese Patent Publication No. 39-2305) or a premixed mixture of a substituted succinic anhydride and a specific surfactant was dispersed in water or an aqueous solution of a specific water-soluble polymer substance. (For example, Japanese Patent Publication No. Sho 53-36044, Japanese Patent Laid-Open No. Sho 58)
-45731, JP-A-59-47498) and the like.

Further, a substituted alkyl succinic anhydride or a substituted alkenyl succinic anhydride or a mixture of these succinic anhydrides [a] 70 to 99.9% by weight, and a polyoxyethylene alkyl ether phosphate ester or polyoxyethylene alkyl aryl It is known that an ether phosphate or a mixture [b] of these phosphates [b] in an amount of 0.1 to 30% by weight is dispersed in an aqueous solution of a water-soluble polymer compound (JP-A-60-28598). ing.

[Problems to be Solved by the Invention] By the way, among the above-mentioned aqueous dispersions of substituted succinic anhydrides, those using cationic starch simply require a large-scale device for dispersing the substituted succinic anhydride in water. In addition, it is difficult to sufficiently reduce the dispersed particle size of the obtained aqueous dispersion, and therefore, there is a drawback in that it is not possible to avoid a slight decrease in size performance.

Further, in the case of using a pre-mixture in which a substituted succinic anhydride and a specific surfactant are pre-mixed, this pre-mixture has poor stability during storage, and the time after preparation of the pre-mixture increases. Not only has a serious drawback that the dispersibility in water is lost and the size performance is lowered, or it cannot be exhibited at all, and particularly, a substituted succinic anhydride having an internal olefin structure suitable as a sizing agent is used. However, some of the substituted succinic anhydrides have the drawback of being poor in dispersibility in water.

In the method of obtaining an aqueous dispersion using the preliminary mixture, when preparing the aqueous dispersion from the preliminary mixture, it is necessary to disperse the preliminary mixture in an aqueous solution in which cationic starch is previously dissolved. For example, an aqueous dispersion with good dilution stability can be obtained, but since the aqueous solution of cationic starch itself is unstable over time, the cationic starch is dissolved in water immediately before using the aqueous dispersion as a sizing agent. In addition, there is a negative factor such as the need for a powerful (large-scale) emulsifying device for the preparation of the above-mentioned aqueous dispersion due to the poor performance of the cationic starch in water dispersion with respect to the substituted succinic anhydride. are doing.

Further, the premix proposed in JP-A-60-28598 has excellent properties with respect to storage stability, which is a drawback of the premix of the substituted succinic anhydride and the surfactant. In addition, it is proposed to have a feature such as a premix which exhibits good dispersibility in water even for a substituted succinic anhydride having an excellent internal olefin structure as a sizing agent. It has been found that there are still some problems when the aqueous dispersion obtained from such a premix is used as a sizing agent on an industrial scale.

That is, when the aqueous dispersion of the preliminary mixture proposed in JP-A-60-28598 contains a cationic starch dissolved in the aqueous phase which is the continuous phase thereof, it is diluted with the aqueous dispersion. Stability is good, but in other cases the dilution stability is insufficient, so when this aqueous dispersion is applied as a sizing agent in the practical papermaking process, wires of paper machines, rolls, blankets, etc. It has a drawback that it may cause stains and make continuous operation impossible for a long time.

The present inventors have found that an aqueous dispersion of a substituted succinic anhydride containing a specific water-soluble copolymer obtained by using (meth) acrylamide and N, N-dialkylaminoalkyl (meth) acrylamide as essential monomer components. However, it was found that the above-mentioned various problems associated with each of the above-mentioned aqueous dispersions are solved (JP-A-61-234927).

However, the aqueous dispersion of the substituted succinic anhydride containing the specific water-soluble copolymer, when used as a sizing agent for papermaking, does not always satisfy the sizing effect in the low addition range of the sizing agent. Not applicable and acidic papermaking process that does not use calcium carbonate filler, or neutral papermaking process of medium quality paper that uses calcium carbonate filler and often adds a small amount of sulfuric acid band In doing so, it was found that the peeling between the wet paper web and the roll in the press section deteriorates, and that a problem of operation occurs that paper breakage easily occurs.

On the other hand, the present invention is a specific water-soluble copolymer obtained by using the above-mentioned (meth) acrylamide and N, N-dialkylaminopropyl (meth) acrylamide as an essential monomer component previously proposed by the present inventors. Actions and effects of the aqueous dispersion of the substituted succinic anhydride containing
In addition to the excellent size effect in the paper manufacturing process and the action such as good dilution stability of the aqueous dispersion, and the effect as it is, the size effect can be sufficiently satisfied even in the low sizing agent addition range. Even in the neutral papermaking process including the acidic papermaking process that does not use calcium carbonate filler and the case where the sulfuric acid band is used, the aqueous solution of the substituted succinic anhydride exhibits excellent operability just like in other cases. It was possible to provide a dispersion.

[Means for Solving the Problems] The present invention provides 50 to 98.5 mol% of (meth) acrylamide (a), 1 to 49.5 mol% of N, N-dimethylaminopropyl (meth) acrylamide (b) and 0.5 to Water consisting of a water-soluble copolymer [A] and a substituted succinic anhydride [B] containing 20 mol% of (meth) acrylic acid (c) as a monomer component, and a polyoxyalkylene alkyl (aryl) ether phosphate ester Contains an oil type surfactant as an essential component, and the average particle size of the emulsion is 0.
It is an aqueous dispersion of a substituted succinic anhydride having a size of 5 μm or less.

As the substituted succinic anhydride [B] in the present invention,
Although any of the known substituted succinic anhydrides in conventional sizing agents can be used, specifically, they have a hydrophobic hydrocarbon group having 8 or more carbon atoms, preferably 12 to 36, such as an alkyl group or an alkenyl group. Substituted succinic anhydride can be used.

The substituted succinic anhydride is generally one which can be easily produced by an addition reaction between maleic anhydride and olefins such as α-olefin having a corresponding number of carbon atoms, internal olefin, or a mixture thereof. Is.

In particular, substituted succinic anhydrides such as octadecene-
9, tetradecene-7, hexadecene-7, eicosene-11 or a mixture thereof, or a straight chain in which double bonds obtained by dehydrogenation of linear paraffins are distributed almost uniformly at each position except the α-position. Internal olefin mixture, the total amount of internal olefins having 2-, 3- and 4-position double bonds obtained by isomerizing linear α-olefin in the presence of a catalyst is 70% or more. In the case of an addition reaction product of a maleic anhydride with a linear internal olefin mixture that is, for example, the substituted succinic anhydride is an alkenylsuccinic anhydride having a succinyl anhydride group inside the substituent. In the case of a product, the sizing effect exhibited by applying it as a papermaking sizing agent is further enhanced.

In the present invention, the monomer component constituting the water-soluble copolymer used together with the substituted succinic anhydride is acrylamide, methacrylamide, or (meth) acrylamide (a) composed of both of these, and N, N-dimethyl. Aminopropyl acrylamide or N, N-dimethylaminopropyl methacrylamide, or N, N-dimethylaminopropyl (meth) acrylamide (b) consisting of both of them, and acrylic acid, methacrylic acid or both of these (meth) Acrylic acid (c).
The N, N-dimethylaminopropyl (meth) acrylamide (b) has the general formula [Wherein R represents hydrogen or a methyl group, and R ¹ and R ² represent a methyl group. ] It is a basic tertiary amino group containing monomer represented by.

The water-soluble copolymer [A] of the present invention comprises (meth) acrylamide (a) 50 to 98.5 mol% and N, N-dimethylaminopropyl (meth) acrylamide (b) 1 to 49.5 mol%.
And (meth) acrylic acid (c) of 0.5 to 20 mol%, and the copolymer [A] is obtained by subjecting the monomer mixture adjusted to the above composition ratio to a usual polymerization operation. It can be easily obtained.

Further, (meth) acrylamide (a) 75 to 94 mol%
And N, N-dimethylaminopropyl (meth) acrylamide (b) 5 to 20 mol% and (meth) acrylic acid (c)
When the aqueous dispersion of the substituted succinic anhydride of the present invention is used as a sizing agent, the copolymer [A] with 1 to 10 mol% has a sizing effect in the low sizing agent addition range, an acidic papermaking step or a medium It has been confirmed that more favorable results are obtained due to good operability in the flexible papermaking process. As the copolymerization method, it is preferable to use an aqueous solution polymerization method, and a water-soluble copolymer [A] having a molecular weight of about 5,000 or more, preferably 20,000 or more is effectively used.

Further, in the present invention, the water-soluble copolymer [A] mixed with the substituted succinic anhydride [B] is the water-soluble copolymer [A].
It may be a water-soluble copolymer (tentatively referred to as [A ₂ ]) in which 70% by weight and another copolymerizable monomer component are mixed,
Further, it may be a mixture of the above [A] and [A ₂ ].

As other copolymerizable monomer component used here,
For example, aromatic vinyl monomers such as styrene and alkylstyrene, α, β-unsaturated carboxylic acid esters such as α, β-unsaturated carboxylic acid alkyl esters, hydroxyalkyl esters and aminoalkyl esters, vinyl acetate and the like. Other fatty acid vinyl esters, other vinyl compounds such as vinyl ether and vinyl amide, allyl alcohols and allyl ethers, allyl compounds such as allylamine and diallylamine and their quaternary ammonium salts, N, N-dialkylaminoalkyl (meth ) Polymerizable quaternary ammonium compounds obtained by quaternizing acrylamide, aminoalkyl (meth) acrylate, vinyl pyridine and the like, and other polymerizable unsaturated compounds are exemplified.

Although the content of the substituted succinic anhydride [B] in the aqueous dispersion of the present invention can be arbitrarily selected, it is generally
A stable aqueous dispersion is obtained in the range of 0.01 to 25% by weight.
In particular, since the aqueous dispersion of the present invention has excellent stability even when it is diluted, it is extremely useful.
The effect brought about by the dilution stability becomes clearer at a concentration of less than or equal to wt%.

When the water-soluble copolymers [A] and [A ₂ ] are mixed, the total content of both is preferably 0.05 to 20% by weight, and is preferably about 1 to 20 parts by weight of the substituted succinic anhydride. It is preferable that the total amount of the water-soluble copolymers [A] and [A ₂ ] is selected within the range of about 0.2 to 2 parts by weight.

Further, it is a matter of course that the aqueous dispersion of the substituted succinic anhydride of the present invention contains an oil-in-water surfactant, and may additionally contain a water-soluble polymer substance. As the oil-in-water surfactant used here, one having compatibility with the substituted succinic anhydride [B] can be used, but it gives the substituted succinic anhydride [B] excellent dispersibility in water, and It is desirable to select and use a surfactant that does not adversely affect the size effect.

For example, as the oil-in-water type surfactant, a sulfuric acid half ester or a phosphoric acid ester of polyoxyalkylene alkyl (arule) ether is suitable. In particular, in the case of an oil-in-water type surfactant comprising a sulfuric acid half ester or a phosphoric acid ester of polyoxyalkylene alkyl (aryl) ether, the dispersed particle size of the substituted succinic anhydride in the aqueous dispersion is extremely fine. Is the most preferred form of the invention.

Particularly preferred oil-in-water surfactants have the general formula [Wherein R ₃ is an alkyl group or an alkylaryl group having 8 or more carbon atoms, X is an alkylene group, A is hydrogen or a group represented by the formula R ^4-
(O—X) ₁ — [wherein R ⁴ represents an alkyl group or an alkylaryl group, X represents an alkylene group, and l represents an integer of 1 or more]
And m represents an integer of 1 or more. ] It is a polyoxyalkylene alkyl (aryl) ether phosphate represented by, and has an extremely excellent compatibility with the substituted succinic anhydride, and further, the substituted succinic anhydride has a particularly excellent dispersibility in water. It is a thing.

Further, R _{3 in} the general formula of the oil-in-water type surfactant is an alkyl group having 10 to 20 carbon atoms or an alkylaryl group, and X
Is an ethylene group, and when the value of m is an integer of 5 or more and an oil-in-water surfactant is used, the dispersed particles in the aqueous dispersion of the substituted succinic anhydride are very small. Therefore, when used as a papermaking sizing agent, the sizing effect exhibited is even more excellent.

The aqueous dispersion of the present invention is prepared as a preliminary mixture by adding the substituted succinic anhydride [B] and the oil-in-water surfactant to an aqueous solution containing the water-soluble copolymer [A]. Further, the content of the oil-in-water type surfactant in the preliminary mixture is appropriately about 0.1 to 10% by weight.

In order to obtain the aqueous dispersion of the present invention, 1 part by weight of the preliminary mixture is used, and when the mixture of the water-soluble copolymer [A] ([A] and [A ₂ ] is used, the sum of both is obtained. It is preferable to use an aqueous solution containing about 0.1 to 2 parts by weight and mix and stir by any procedure. Mixing using a stirrer such as a general propeller stirrer, various other homogenizers and mixers. Good.

The aqueous dispersion of the substituted succinic anhydride of the present invention is mainly used as a sizing agent for papermaking, but it can also be used as a sizing agent in various textile industries. Incidentally, also in the use as a sizing agent for papermaking, the aqueous dispersion of the substituted succinic anhydride is adjusted to any desired concentration, and it is added as an internal sizing to the pulp slurry which is a raw material for papermaking, or as a sheet. It can be applied to any papermaking process such as acidic papermaking in which a sulfuric acid band is used together or neutral papermaking in which a sulfuric acid band is not used for surface sizing applied to a wet or dry sheet after formation by any means.

[Operation] The present invention has the constitution as described above, and is a water-soluble copolymer [A] added and contained in an aqueous dispersion.
Is capable of exhibiting high adsorptivity for pulp,
In addition, the action of the oil-in-water type surfactant exerts the action of efficiently fixing the particulate succinic anhydride in the dispersion liquid on the pulp fiber surface.

Further, the water-soluble copolymer [A] in the aqueous dispersion of the present invention
The dispersibility in water that the substituted succinic anhydride [B] brings is
It is far superior to the copolymer of (meth) acrylamide (a) and N, N-dialkylaminoalkyl (meth) acrylamide (b), and the action of the water-soluble copolymer [A] is Which provides a very high dilution stability to the aqueous dispersion of the substituted succinic anhydride of the present invention.

Further, the water-soluble copolymer [A] contained in the aqueous dispersion of the present invention has a carboxyl group based on the (meth) acrylic acid monomer component contained in the water-soluble copolymer [A]. ,, since it has a reactivity between the aluminum polyvalent cation in the sulfuric acid band, when applied as a papermaking sizing agent in the papermaking process containing a sulfuric acid band, between the carboxyl group and the aluminum polyvalent cation An excellent fixing effect is exhibited by the interaction, and therefore, in addition to the excellent size effect, various troubles such as contaminating the wire, roll, blanket and the like of the paper machine in the papermaking process can be avoided.

[Examples] Hereinafter, an aqueous dispersion of a substituted succinic anhydride according to the present invention and a method for producing the same will be described with reference to Examples, and a comparative example will be described together with a specific configuration of the aqueous dispersion of a substituted succinic anhydride. And properties will be described.

Example Each part by weight of the surfactant shown in the predetermined column of Table 1 was added to 100 parts by weight of alkenylsuccinic anhydride, and the mixture was stirred and mixed at room temperature to obtain a composition of alkenylsuccinic anhydride. It was The alkenyl succinic anhydride is obtained by reacting maleic anhydride with an internal olefin containing 90% by weight of an olefin having a carbon number of 15 to 18 and having a double bond at the 2 to 4 positions according to a conventional method.

Then, each of the alkenylsuccinic anhydrides was mixed in each part by weight of a 10% by weight solution of a water-soluble polymer compound, which is also shown in the predetermined column of Table 1, and a homomixer [Special Machine Industry ( Co., Ltd .: HV: M type] and stirred at 50 V for 1 minute to prepare respective aqueous dispersions of substituted succinic anhydride.

Experiment 1 Each of the aqueous dispersions obtained in the above Examples and Comparative Examples was mixed with 20% by weight of heavy calcium carbonate filler based on the weight of pulp [Sankyo Milling Co., Ltd .: Escalon # 800],
Similarly, a 2% by weight pulp slurry [L-BKP, csf400 containing 1% by weight of gelatinized cationic starch based on the weight of pulp.
cc], the composition of the substituted succinic anhydride and the surfactant in the aqueous dispersion is added so as to be 0.15% by weight of the weight of the pulp, and the tapi standard paper machine (TAPP standard paper machine (TAPP
I Standard Sheet machine), after adjusting a hand paper equivalent to 80 g / m ² , it is dried with a rotary dryer at 110 ° C for 120 seconds,
I got handmade paper.

Table 2 shows the Steckigt sizing degree (seconds) measured after conditioning the obtained handmade paper according to JIS. In addition, in Table 2,
The average particle diameter (μm) of the emulsion in the aqueous dispersion after leaving each aqueous dispersion for 10 hours, the composition of the alkenyl succinic anhydride and the surfactant was 0.05 in tap water with a total hardness of 100. The stability of the dispersion liquid diluted to be wt% is also shown.

Experiment 2 Each of the aqueous dispersions obtained in the above Examples and Comparative Examples was treated with 20% by weight of talc of pulp and 0.5% by weight of sulfuric acid band [Al ₂ (SO _{2
4) 0 · 16~18H 2 O]} 2 % by weight containing a pulp slurry [L-BKP, during csf400cc], the compositions of the substituted succinic anhydride and surfactant in the aqueous dispersion is It was added so as to be 0.1% by weight of the pulp weight, and hand paper was obtained in the same manner as in Experiment 1 below. Table 3 shows the Steckigt sizing degree (seconds) of the obtained handmade paper measured after humidity conditioning according to JIS.

Experiment 3 In a pulp slurry having the same composition as that used in Experiment 2, the composition of the substituted succinic anhydride and the surfactant in each of the aqueous dispersions obtained in the above-mentioned Examples and Comparative Examples was such that the pulp weight was It was added so as to be 1% by weight, and thereafter, paper was made in the same manner as in Experiment 1 to prepare a wet sheet. Each wet sheet obtained was sandwiched between a chrome-plated plate and filter paper, and 3.
After water was pressed under a pressure of 5 kg / cm ² for 5 minutes, the wet sheet was peeled from the plate, and stains (presence or absence of deposits such as fine fibers) on the plate surface were visually observed. The results are shown in Table 4.

[Effects of the Invention] As described above, the aqueous dispersion of the substituted succinic anhydride of the present invention has the stabilizing effect of the water-soluble copolymer [A], and thus the conventional substituted succinic anhydride utilizing cationic starch is used. It has the same dilution stability as the aqueous dispersion,
Moreover, it is used as a sizing agent in the papermaking process because it is an aqueous dispersion having a finer emulsion particle size than the emulsion particle size in an aqueous dispersion of a substituted succinic anhydride using a conventional synthetic polymer. In this case, the amount of the substituted succinic anhydride added is, for example, 0.
Even in the low addition range of 5% by weight or less, a satisfactory size effect can be obtained.

Further, the aqueous dispersion of the substituted succinic anhydride of the present invention,
In the neutral papermaking process including the case where an acidic papermaking process not using calcium carbonate or a sulfuric acid band is used, since the fixing action to the pulp fiber becomes more excellent, any papermaking process including the papermaking process using the sulfuric acid band In addition to obtaining an excellent size effect, the paper can be produced without inducing stains on wires, rolls, blankets and the like of the paper machine, and therefore excellent workability can be provided.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication location D21H 17/14 17/37 (72) Inventor Hideto Yamada 1-5-16 Oji, Akashi-shi, Hyogo No. 404 (72) Inventor Akihiro Yata 2-8 Higashishinmachi, Nagaoka City, Niigata Prefecture (72) Inventor Naotake Sato 1-22-12 Nakatehara, Kohoku Ward, Yokohama City, Kanagawa Prefecture (56) Reference JP-A-58-45730 (JP, A) JP 58-45731 (JP, A) JP 58-120897 (JP, A) JP 60-28598 (JP, A)

Claims (2)

[Claims] 1. 50 to 98.5 mol% of (meth) acrylamide (a), 1 to 49.5 mol% of N, N-dimethylaminopropyl (meth) acrylamide (b) and 0.5 to 20 mol% of (meth) acryl. Containing a water-soluble copolymer [A] containing an acid (c) as a monomer component, a substituted succinic anhydride [B], and an oil-in-water surfactant composed of a polyoxyalkylene alkyl (aryl) ether phosphate ester An aqueous dispersion of a substituted succinic anhydride, characterized in that the emulsion has an average particle size of 0.5 μm or less. 2. An aqueous dispersion of a substituted succinic anhydride according to claim 1, wherein the substituted succinic anhydride is an alkenyl succinic anhydride.