Our overshoes and rubber shoes will wear hard and become brittle and easy to crack. This phenomenon is called aging of rubber. Rubber aging is a very complex problem. In general, oxidation, sunlight and high temperatures can cause rubber to age.
The hometown of rubber is South America, and the local Indians call it the tears of the tree. Because the skin of the rubber tree is cut, white latex will flow out like a tree in tears. At first, people added a little acetic acid to the latex and condensed into a solid substance. This is raw rubber. The molecular structure of the raw rubber is a linear structure like a single chain, and the strength is not high. Although it is elastic, it is easy to break. Especially sensitive to changes in temperature, a heat will become soft and sticky, and a cold will become hard and brittle. In rubber processing plants, people began to use sulfur to revolutionize the appearance of raw rubber. The sulfur atom can connect the rubber molecules to each other, and the linear structure of the rubber molecules becomes a network structure, thereby greatly increasing the strength of the rubber. In the rubber processing, in addition to the addition of a vulcanizing agent, a coloring agent, a softening agent, a reinforcing agent, a filler, an antioxidant, and the like are added.
The sun contains a lot of ultraviolet rays, and in addition to being able to sterilize and cure ultraviolet rays, it is also a "pecker." When it is drilled into the interior of the rubber product, the molecular chain of the rubber is cut. At the same time, the high heat of the sun will separate the sulfur atom from the raw rubber and destroy its molecular structure. As a result, the rubber loses its elasticity and the intermolecular bond, so the crack is damaged.
Therefore, when you pass the overshoes and rubber shoes, wash them immediately, put them in a dark and ventilated place to dry, do not expose to the sun or bake at the stove, and do not touch kerosene and gasoline, because oil The molecules of the class will be drilled into the rubber molecules, which will expand the rubber molecules and cause the rubber shoes to swell and deform.