CN112933667B

CN112933667B - Antifoaming agent for carboxylic acrylonitrile butadiene latex and preparation method thereof

Info

Publication number: CN112933667B
Application number: CN202110125126.1A
Authority: CN
Inventors: 张荣召
Original assignee: Shandong University of Technology
Current assignee: Shandong University of Technology
Priority date: 2021-01-29
Filing date: 2021-01-29
Publication date: 2022-08-09
Anticipated expiration: 2041-01-29
Also published as: CN112933667A

Abstract

The invention belongs to the technical field of industrial defoaming agents, and particularly relates to a defoaming agent for carboxylated nitrile latex and a preparation method of the defoaming agent. The defoaming agent for the carboxylated nitrile latex is prepared from the following raw materials in parts by weight: 10-20 parts of polysiloxane; 2-10 parts of white carbon black; 1-5 parts of an emulsifier; 100 parts of deionized water; the preparation method comprises the following steps: and (3) sequentially adding polysiloxane and white carbon black into the reaction kettle, heating to 110-140 ℃, reacting for 3-6 hours, cooling to 60-90 ℃, adding an emulsifier and deionized water, reacting for 20-50 minutes, and cooling to room temperature to obtain the product. The defoaming agent is a polysiloxane emulsion type defoaming agent, is mainly used for eliminating foam in the production process of carboxyl butyronitrile latex, is particularly suitable for foam in the monomer removal process after polymerization, and has the advantages of small using amount, quick defoaming, excellent foam inhibition and no latex gel; the preparation method is scientific, reasonable, simple and feasible.

Description

Antifoaming agent for carboxylic acrylonitrile butadiene latex and preparation method thereof

Technical Field

The invention belongs to the technical field of industrial defoaming agents, and particularly relates to a defoaming agent for carboxylated nitrile latex and a preparation method of the defoaming agent.

Background

Carboxyl latex plays an extremely important role in the modern latex industry, and carboxyl butyronitrile latex is developed as a modified variety of butyronitrile latex. Compared with the common butyronitrile latex, the carboxylic butyronitrile latex has outstanding mechanical stability, flowability, high tensile strength and unique adhesion. Therefore, the carboxylated nitrile latex has been developed rapidly in recent years, and is widely applied to industries such as thick, thin, underwear-containing and underwear-free gloves, condoms, sealing materials and the like. A large amount of foam can be generated under the action of adding an emulsifier and an initiator and stirring in the polymerization process of the carboxyl butyronitrile latex, and simultaneously, a large amount of foam can be generated when discharging materials for polymerization and removing monomers and adjusting the pH value, so that the normal production is seriously influenced. Therefore, in the production process of the carboxylic acrylonitrile butadiene latex, a defoaming agent needs to be added in time to reduce foam in the production process.

At present, the existing defoamer for carboxylic acrylonitrile butadiene latex has the problems of poor defoaming effect, poor foam inhibition effect and stability, easy latex gel agglomeration in the using process and the like. Accordingly, there is a need for improvements and developments in the art.

Disclosure of Invention

In view of the defects of the prior art, the invention aims to provide the defoaming agent for the carboxylated nitrile latex, which has the advantages of small using amount, quick defoaming, excellent foam inhibition performance and no gel generation of the carboxylated nitrile latex in the defoaming process; the invention also provides a preparation method of the composition, which is scientific, reasonable, simple and feasible.

The defoaming agent for the carboxylated nitrile latex is prepared from the following raw materials in parts by weight:

wherein:

the viscosity of the polysiloxane is 350-1000 mPas.

The specific surface area of the white carbon black is 150-380m ² /g。

The emulsifier is one or more of span 20, span 40, span 60, span 65, span 80, span 85, Tween 20, Tween 40, Tween 60, Tween 65, Tween 80 or Tween 85.

The preparation method of the defoaming agent for the carboxylated nitrile latex comprises the following steps:

and (3) sequentially adding polysiloxane and white carbon black into the reaction kettle, heating to 110-140 ℃, reacting for 3-6 hours, cooling to 60-90 ℃, adding an emulsifier and deionized water, reacting for 20-50 minutes, and cooling to room temperature to obtain the product.

Compared with the prior art, the invention has the following beneficial effects:

1. the carboxyl butyronitrile latex defoamer is a polysiloxane emulsion defoamer, is mainly used for eliminating foam in the production of carboxyl butyronitrile latex, is especially suitable for foam in the monomer removing process after polymerization, and has the advantages of less consumption, quick defoaming, excellent foam inhibition performance and no gel generation of the carboxyl butyronitrile latex in the defoaming process.

2. The preparation method is scientific, reasonable, simple and feasible.

Detailed Description

The present invention provides an antifoaming agent for carboxylated nitrile latex, and the present invention will be described in further detail below in order to make the object, technical scheme and effect of the present invention clearer and clearer. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Example 1

the preparation process comprises the following steps:

and (3) sequentially adding polysiloxane and white carbon black into the reaction kettle, heating to 110 ℃, reacting for 6 hours, cooling to 60 ℃, adding an emulsifier and deionized water, reacting for 50 minutes, and cooling to room temperature to obtain the product.

Example 2

the preparation process comprises the following steps: and (3) sequentially adding polysiloxane and white carbon black into the reaction kettle, heating to 140 ℃, reacting for 5 hours, cooling to 80 ℃, adding an emulsifier and deionized water, reacting for 40 minutes, and cooling to room temperature to obtain the product.

Example 3

the preparation process comprises the following steps: and (3) sequentially adding polysiloxane and white carbon black into the reaction kettle, heating to 130 ℃, reacting for 5 hours, cooling to 80 ℃, adding an emulsifier and deionized water, reacting for 50 minutes, and cooling to room temperature to obtain the product.

Example 4

the preparation process comprises the following steps: and (3) sequentially adding polysiloxane and white carbon black into the reaction kettle, heating to 140 ℃, reacting for 6 hours, cooling to 70 ℃, adding an emulsifier and deionized water, reacting for 20 minutes, and cooling to room temperature to obtain the product.

Testing of defoaming agent Performance

The defoaming agents prepared in examples 1 to 4 and the commercially available defoaming agent A, B, C were used for defoaming performance tests. Putting a 1000mL measuring cylinder into a constant-temperature water bath at 60 ℃, adding 100mL of carboxylated nitrile latex produced by a polymerization device, starting a bubbler, stopping bubbling when foam reaches 500mL, simultaneously adding 0.01g of defoaming agent, and recording the foam elimination time, wherein the obtained time is the defoaming time. The bubbler was turned on and the time required when the foam reached 300mL was the foam suppression time. And observing whether the carboxylated nitrile latex added with the defoaming agent is agglomerated or not when the carboxylated nitrile latex is stabilized for 30min at the temperature of 60 ℃ and cooled to room temperature. The test results are shown in Table 1.

TABLE 1

Serial number	Defoaming time/s	Foam inhibition time/s	Whether or not to agglomerate
				Example 1	6	1000	Whether or not
Example 2	8	950	Whether or not
				Example 3	3	1200	Whether or not
Example 4	4	1100	Whether or not
				Antifoam agent A	5	800	Is that
Defoaming agent B	6	650	Is that
				Antifoam agent C	7	700	Is that

It is to be understood that the invention is not limited to the examples described above, but that modifications and variations may be effected thereto by those of ordinary skill in the art in light of the foregoing description, and that all such modifications and variations are intended to be within the scope of the invention as defined by the appended claims.

Claims

1. The antifoaming agent for the carboxylic nitrile latex is characterized in that: the feed is prepared from the following raw materials in parts by weight:

2. the antifoaming agent for carboxylated nitrile latex according to claim 1, wherein: the viscosity of the polysiloxane is 350-1000 mPas.

3. The antifoaming agent for carboxylated nitrile latex according to claim 1, wherein: the specific surface area of the white carbon black is 150-380m ² /g。

4. The antifoaming agent for carboxylated nitrile latex according to claim 1, wherein: the emulsifier is one or more of span 20, span 40, span 60, span 65, span 80, span 85, Tween 20, Tween 40, Tween 60, Tween 65, Tween 80 or Tween 85.

5. A process for the preparation of an antifoaming agent for carboxylated nitrile latex according to any of claims 1 to 4, characterized in that: the method comprises the following steps: