High-strength self-healing capsule and production process thereof

Patent metadata

Field	Value
Publication number	US-2024254057-A1
Application number	US-202218017707-A
Country	US
Kind code	A1
Filing date	Jul 28, 2022
Priority date	Dec 30, 2021
Publication date	Aug 1, 2024
Grant date	—

Abstract

Provided is a high-strength self-healing capsule and a supporting production process thereof, belongs to the field of self-healing of concrete, comprising: healing agent and maltose; further comprising: mixing cement, silica fume and expansive materials evenly to obtain healing agent powder; mixing the healing agent powder with maltose to obtain healing agent composite powder; pre-pressing the healing agent composite powder to form fine granules; sieving the fine granules made from the pre-pressing, and granulating to obtain capsule core granules; and spraying polyvinyl alcohol (PVA) solution to the capsule core granules, while blowing hot air to remove moisture on the surface of the capsule core granules, for the PVA solution to form a film on the surface of the capsule core granules, drying, and then obtaining. On the basis of the process of the present invention, according to the engineering service environment and use requirements of the cement-based materials, suitable healing agent raw materials can be selected and combined to efficiently produce capsules, so that they can play a targeted role in self-healing.

First claim

1 . A high-strength self-healing capsule, comprising: healing agent and maltose;
and, a method for preparing the high-strength self-healing capsule, comprising: mixing cement, silica fume and expansive materials evenly to obtain healing agent powder; mixing the healing agent powder with the maltose to obtain healing agent composite powder; pre-pressing the healing agent composite powder to form fine granules; sieving the fine granules made from the pre-pressing, and granulating to obtain capsule core granules; and spraying polyvinyl alcohol (PVA) solution to the capsule core granules, while blowing hot air to remove moisture on a surface of the capsule core granules, for the PVA solution to form a film on the surface of the capsule core granules, and then obtaining the high-strength self-healing capsule after drying.

2 . The high-strength self-healing capsule according to claim 1 , wherein an added amount of the maltose is 3-10% of a total mass of the healing agent powder.

3 . The high-strength self-healing capsule according to claim 1 , wherein the expansive material may be replaced with macromolecule water absorbing resin or expanded rubber powder.

4 . The high-strength self-healing capsule according to claim 1 , wherein a granule size of the capsule core granule is 1-5 mm.

5 . The high-strength self-healing capsule according to claim 1 , wherein conditions of the granulating are: a pressure degree is 30-60 kN, and a rotary speed is 10-40 r/min.

6 . The high-strength self-healing capsule according to claim 1 , wherein a pressure of the pre-pressing is 0-10 MPa.

7 . The high-strength self-healing capsule according to claim 1 , wherein a mesh diameter of a screen for sieving the fine granules is 0.12-0.18 mm.

8 . The high-strength self-healing capsule according to claim 1 , wherein a concentration of the PVA solution is 5-10%.

9 . The high-strength self-healing capsule according to claim 1 , wherein a temperature of the hot air is 40-70° C.

10 . The high-strength self-healing capsule according to claim 1 , wherein a condition of the drying is drying for 2-3 hours at 40-50° C.

11 . An application of the high-strength self-healing capsule of claim 1 in a self-healing of concrete.

Assignees

• Univ Shandong

Inventors

• Chang Honglei
• Liu Jian
• Xie Quanyi

Classifications

• C04B40/0633

  Chemical separation of ingredients, e.g. slowly soluble activator · CPC title

• C04B40/0046 Primary

  characterised by their processing, e.g. sequence of mixing the ingredients when preparing the premixtures · CPC title

• C04B40/0675

  Mortars activated by rain, percolating or sucked-up water; Self-healing mortars or concrete · CPC title

• C04B20/1033 Primary

  obtained by reactions only involving carbon-to-carbon unsaturated bonds · CPC title

• C04B18/021 Primary

  agglomerated by a mineral binder, e.g. cement · CPC title