阅读说明：本技术 一种复合型泡沫混凝土发泡剂的制备方法 (Preparation method of composite type foam concrete foaming agent ) 是由 瑭规旦 詹浩 于 2018-06-15 设计创作，主要内容包括：本发明公开了一种复合型泡沫混凝土发泡剂的制备方法,先将大豆分离蛋白加至水中制成大豆蛋白溶液并进行预处理,然后向预处理的大豆蛋白溶液中加入木瓜蛋白酶和纤维素酶进行水解反应,得到大豆蛋白发泡剂溶液；最后在大豆蛋白发泡剂溶液中加入柠檬酸、表面活性剂、稳定剂、聚乙烯醇,分散,即得。本发明所制备的泡沫混凝土发泡剂发泡性能好和稳定性强,且本发明制备工艺简单,工序简便,容易操作,实用性强。(The invention discloses a preparation method of a composite type foam concrete foaming agent, which comprises the steps of adding soybean protein isolate into water to prepare a soybean protein solution, carrying out pretreatment, adding papain and cellulase into the pretreated soybean protein solution, and carrying out hydrolysis reaction to obtain a soybean protein foaming agent solution; and finally, adding citric acid, a surfactant, a stabilizer and polyvinyl alcohol into the soybean protein foaming agent solution, and dispersing to obtain the soybean protein foaming agent. The foam concrete foaming agent prepared by the invention has good foaming performance and strong stability, and the preparation process is simple, the working procedure is simple and convenient, the operation is easy, and the practicability is strong.)

1. A preparation method of a compound type foam concrete foaming agent is characterized by comprising the following steps: the method comprises the following steps:

step 1, adding soy protein isolate into water to prepare a soy protein solution, dropwise adding an inorganic alkali solution, heating in a water bath at 70 ℃ for 15-30min, and carrying out pretreatment;

step 2, adding 0.3-0.5wt.% of papain and 0.05-0.1wt.% of cellulase into the pretreated soybean protein solution, adjusting the pH of the solution to 7.0, performing hydrolysis reaction, heating to inactivate the enzyme after the reaction is finished, cooling the solution, centrifuging, and filtering to obtain a soybean protein foaming agent solution;

and 3, adding 0.3-0.5wt.% of citric acid into the soybean protein foaming agent solution, stirring, adding 5-10 wt.% of surfactant, 2-4 wt.% of stabilizer and 0.5-1 wt.% of polyvinyl alcohol, and dispersing to obtain the soybean protein foaming agent.

2. The preparation method of the composite type foam concrete foaming agent according to claim 1, characterized in that: in the step 1, the concentration of the soybean protein solution is 5-10 wt.%, the concentration of the inorganic alkali solution is 0.1-0.2 wt.%, and the volume ratio of the soybean protein solution to the inorganic alkali solution is 100: 2-5.

3. The preparation method of the composite type foam concrete foaming agent according to claim 1, characterized in that: the hydrolysis reaction in the step 2 is carried out at 50-55 ℃ for 2-3 h.

4. The preparation method of the composite type foam concrete foaming agent according to claim 1, characterized in that: the surfactant is selected from a mixture of two of alpha-sodium alkenyl sulfonate, sodium dodecyl sulfate, sodium dodecyl benzene sulfonate, sodium fatty alcohol-polyoxyethylene ether sulfate or cocamidopropyl betaine.

5. The preparation method of the composite type foam concrete foaming agent according to claim 1, characterized in that: the stabilizer is one or a mixture of several of dodecanol, cellulose ether or polyacrylamide.

6. The preparation method of the composite type foam concrete foaming agent according to claim 1, characterized in that: the cellulose ether is selected from hydroxyethyl cellulose, methyl cellulose or ethyl fiber.

Technical Field

The invention belongs to the technical field of building materials, and particularly relates to a preparation method of a composite type foam concrete foaming agent.

Background

The foam concrete is also called as foam concrete, and the foam holes are formed in the concrete, so that the concrete achieves the effects of light weight, heat preservation and heat insulation. The foam concrete is mainly prepared by preparing a foaming agent into foam by a mechanical method and then uniformly stirring the prepared foam and concrete slurry, so that the foaming performance and the foam stability of the foaming agent have great limitation on the performance of the foam concrete.

At present, the foaming agent mainly comprises a rosin type foaming agent, a surfactant type foaming agent, a plant type foaming agent, an animal type foaming agent and a composite type foaming agent. The traditional rosin type foaming agent has the advantages of low price, convenience and easy obtainment, but is not suitable for producing low-density products below 700kg/m3 level due to poor stability; protein foaming agents, due to high requirements on synthesis technology, are difficult to achieve the quality of foreign products so far, and are only applied in a small amount at present because of high cost. The surfactant foaming agent has large foaming times and is easy to foam, but has large foam diameter, thin foam wall, quick defoaming and poor stability. Generally, the existing concrete foaming agent is not ideal in foam stability, uniformity and dispersibility, and the foaming agent needs to be developed from a single component to a compound type.

Disclosure of Invention

The invention aims to provide a preparation method of a composite type foam concrete foaming agent, and the obtained foaming agent is good in foaming performance and strong in stability.

A preparation method of a composite type foam concrete foaming agent comprises the following steps:

step 1, adding soy protein isolate into water to prepare a soy protein solution, dropwise adding an inorganic alkali solution, heating in a water bath at 70 ℃ for 15-30min, and carrying out pretreatment;

step 2, adding 0.3-0.5wt.% of papain and 0.05-0.1wt.% of cellulase into the pretreated soybean protein solution, adjusting the pH of the solution to 7.0, performing hydrolysis reaction, heating to inactivate the enzyme after the reaction is finished, cooling the solution, centrifuging, and filtering to obtain a soybean protein foaming agent solution;

and 3, adding 0.3-0.5wt.% of citric acid into the soybean protein foaming agent solution, stirring, adding 5-10 wt.% of surfactant, 2-4 wt.% of stabilizer and 0.5-1 wt.% of polyvinyl alcohol, and dispersing to obtain the soybean protein foaming agent.

Preferably, the concentration of the soy protein solution in step 1 is 5-10 wt.%, the concentration of the inorganic base solution is 0.1-0.2 wt.%, and the volume ratio of the soy protein solution to the inorganic base solution is 100: 2-5.

Preferably, the hydrolysis reaction in step 2 is carried out at 50-55 deg.C for 2-3 h.

Preferably, the surfactant is selected from a mixture of two of sodium alpha-alkenyl sulfonate, sodium dodecyl sulfate, sodium dodecyl benzene sulfonate, sodium fatty alcohol polyoxyethylene ether sulfate or cocamidopropyl betaine.

Preferably, the stabilizer is one or a mixture of several of dodecanol, cellulose ether or polyacrylamide.

Preferably, the cellulose ether is selected from hydroxyethyl cellulose, methyl cellulose or ethyl fiber.

The composite type foam concrete foaming agent is prepared by compounding the soybean protein serving as a base material and a surfactant, and has good foaming performance and strong stability.

Detailed Description