Traditional Culture Encyclopedia - Weather forecast - What does it mean that sponges foam when put into water?

What does it mean that sponges foam when put into water?

1, indicating that there is air in the sponge. Sponges have countless small holes. For a sponge, water is an immersion liquid. When the sponge meets water, the water will soak the sponge, and the liquid level in the pores is concave. The concave liquid exerts a pulling force on the liquid level below, so that the liquid below rises along the pipe wall. When the upward pulling force is equal to the gravity of the liquid column in the tube, the liquid in the tube stops rising, forming capillary phenomenon, and water will fill the sponge gap. The process of sponge absorption is physical change. No chemical changes have taken place.

2. Sponge is a porous material with good water absorption, which can be used for cleaning articles. Commonly used sponges are made of lignocellulosic fibers or foamed plastic polymers. In addition, there are natural sponges made of sponges, which are mostly used for body cleaning or painting. There are also three kinds of synthetic sponges made of other materials, namely low-density polyether (non-absorbent sponge), polyvinyl alcohol (super absorbent material without obvious pores) and polyester.

Production technology:

1. Mix foaming resin, foaming assistant and adhesive resin (to make the finished product sticky).

2. Foaming processing. 80 parts of ethylene vinyl acetate (EVA), 20 parts of APAOPT3385, 20 parts of azodicarbonamide, CaCO and 0.6 part of dicumyl peroxide were mixed together, foamed in a mold, and closed pores were destroyed by mechanical force, thus preparing foam sponge. Its density (d) is 0.028 g/cm, and its 25% compressive hardness is 65438 0.9 kPa.